My father-in-law had a stroke.
Mine had one in his mid-80s. It didn't seem to affect his ability to think and understand conversation, but he became unable to speak. That was a major problem, since like most men born before the advent of computers, he never learned to type. He lived several more years and ultimately died from a variety of symptoms.
My mother, on the other hand, had a much more massive stroke--several years after my father's demise. Her neighbors began to notice that they hadn't seen her come outside for several days, so they called the police. They found her lying on the floor. She was breathing, and all-in-all wasn't in terribly bad condition, so they simply had her sent to the local hospital.
We realized, belatedly, that she was hoping that no one would find her, so she could die peacefully of starvation. We put her in a rest home, for lack of an alternative. She could talk just fine, but she had lost a lot of her memory so conversation was a bit off-base. The first time my (second) wife and I came to visit her, she stared at her for quite a while, with a quizzical look on her face. Wife finally asked her if she even knew her, and very tentatively, she called her by my first wife's name. She had lost 30 years of memories.
Things have a way of going their own way. When we filled out all the documents in the rest home, we made it clear that she was not ever to be fed by a tube, which is a hell of a way to get nutrition. Several days later, the facility called us (by this time we had moved 700 miles away from the facility) to give us the sad news that she had died. Naturally, we asked about the cause of death, and we were perplexed when no one there seemed to want to tell us. We kept harassing them, and finally some poor clerk was given the job of explaining to us that she died during a tube-feeding session. Obviously, the facility was simply trying to keep her alive as long as possible, since we were paying by the day.